1. Field of the Invention
The present invention relates to a polysilane monomolecular film and polysilane built-up film which can be used as various materials such as a material of a layer for migrating holes and electric charges, that is to say, a hole-charge-transfer layer, a light sensitive material used in a photolithography, a non-linear optical material, a piezoelectric material, and a pyroelectric material.
2. Description of the Related Art
Vigorous researches are being made in an attempt to achieve application of a polysilane in various fields including, for example, an electrically conductive material, a precursor material of ceramics, a photoconductive material, a semiconductor material and a nonlinear optical material. Nowadays, a polysilane is a substance of deep interest in the industries.
A polysilane is generally used in the form of a thin film as the material described above. A spin coating method is widely employed for forming a polysilane thin film. In the conventional spin coating method, a polysilane having a Si-Si backbone, that is to say, a Si-Si main chain is dissolved in an organic solvent so as to prepare a polymer solution. A desired substrate is coated with the polymer solution by using a spinner, followed by evaporating the solvent so as to form a polysilane thin film.
However, the conventional spin coating method is poor in its capability of controlling the structure of the formed thin film. Particularly, where a polysilane thin film having a thickness of 0.1 .mu.m or less is formed on a substrate by the conventional spin coating method, the resultant thin film lacks in uniformity and regularity of the molecular orientation.